4-Character 5 x 7 Dot Matrix / RoHS Compliant - By Exemption (see page 1) Serial Input Alphanumeric Industrial Display Sunlight Viewable: ISD235X ISD201X, ISD231X, ISD235X ISD201X ISD231X ISD235X RoHS Compliant - By ExemptionDESCRIPTION FEATURES * Four Dot Matrix Characters * Character Height ISD201X-- 3.81 mm (0.150") ISD231X-- 5.08 mm (0.200") ISD235X-- 5.08 mm (0.200") * Built-in CMOS Shift Registers with Constant Current LED Row Drivers * Wide Viewing Angle * Shift Registers Allow Custom Fonts * Easily Cascaded for Multiple Displays * TTL Compatible * End Stackable * Operating Temperature Range: -55C to +100C * Categorized for Luminous Intensity * Ceramic Package, Hermetically Sealed Flat Glass Window The ISD201X/231X/235X are four digit 5 x 7 dot matrix serial input alphanumeric displays. The displays are available in red, yellow, high efficiency red, or high efficiency green. The package is a standard twelve-pin hermetic DIP with glass lens. The display can be stacked horizontally or vertically to form messages of any length. These displays have two fourteen-bit CMOS shift registers with built-in row drivers. These shift registers drive twenty-eight rows and enable the design of customized fonts. Cascading multiple displays is possible because of the Data In and Data Out pins. Data In and Out are easily input with the clock signal and displayed in parallel on the row drivers. Data Out represents the output of the 7th bit of digit number four shift register. The shift register is level triggered. The like columns of each character in a display cluster are tied to a single pin (see Block Diagram). High true data in the shift register enables the output current mirror driver stage associated with each row of LEDs in the 5 x 7 diode array. The TTL compatible VB input may either be tied to VCC for maximum display intensity or pulse width modulated to achieve intensity control and reduce power consumption. In the normal mode of operation, input data for digit four, column one is loaded into the seven on-board shift register locations one through seven. Column one data for digits 3, 2 and 1 is shifted into the display shift register locations. Then column one input is enabled for an appropriate period of time, T. A similar process is repeated for columns 2, 3, 4 and 5. If the decode time and load data time into the shift register is t, then with five columns, each column of the display is operating at a duty factor of: RoHS Compliance The ISD201X, ISD231X, ISD235X Intelligent DisplaysTM are hermetically sealed displays using a ceramic and glass construction. These components are not lead (Pb) free but are RoHS Compliant based on the RoHS Compliance Directive's Annex, paragraphs 5 and 7. These exemptions allow for lead (Pb) in glass and ceramic electronic components. Refer to the following excerpts from the RoHS Compliance Directive Annex: T DF = -------------------5 (T + 1 ) Applications of lead, mercury, cadmium and hexavalent chromium, which are exempted from the requirements of Article 4(1) T+t, allotted to each display column, is generally chosen to provide the maximum duty factor consistent with the minimum refresh rate necessary to achieve a flicker free display. For most strobed display systems, each column of the display should be refreshed (turned on) at a minimum rate of 100 times per second. With columns to be addressed, this refresh rate then gives a value for the time T+t of: 1 [5 x (100)]=2.0 msec. If the device is operated at 5.0 MHz clock rate maximum, it is possible to maintain t